Problem: Reduce to lowest terms: $- \dfrac{9}{7} \div - \dfrac{1}{4} = {?}$
Answer: Dividing by a fraction is the same as multiplying by the reciprocal of the fraction. The reciprocal of $- \dfrac{1}{4}$ is $- \dfrac{4}{1}$ Therefore: $ - \dfrac{9}{7} \div - \dfrac{1}{4} = - \dfrac{9}{7} \times - \dfrac{4}{1} $ $ \phantom{- \dfrac{9}{7} \times - \dfrac{4}{1}} = \dfrac{-9 \times -4}{7 \times 1} $ $ \phantom{- \dfrac{9}{7} \times - \dfrac{4}{1}} = \dfrac{36}{7} $